Pistol caliber AR-15/M-16-style rifles have long been popular firearms. Pistol ammunition is considerably less expensive than rifle ammunition. In addition, recoil and report are greatly reduced with pistol ammunition compared to rifle ammunition. As a result, pistol caliber AR-15/M-16-style rifles are popular for target shooting, new shooters, and shooters of slight build.
A variety of AR-15/M-16-style rifle conversion kits exist to enable different calibers of ammunition to be fired. Many shooters who already owned Glock® pistols would like to be able to use Glock® pistol magazines in a converted AR-15/M-16-style rifle. Currently, the preferred method for accomplishing this objective is to use a dedicated lower receiver that is specially designed to accept Glock® pistol magazines. Not only is this more expensive than using a standard lower receiver, but the last round hold open mechanism is either rendered inoperable, or works inconsistently, and can require replacing the standard bolt catch spring with a weaker spring. The standard bolt also often requires modification so it will not rub on the feed lips of the magazine.
Although magazine well adapters that enable the use of Glock® magazines in a standard mil spec AR-15/M-16-style rifle lower receiver have been developed, they have not met with widespread commercial success and have either been discontinued or are not routinely available. Prior art magazine well adapters for pistol caliber magazines are prone to vibrating loose during operation and can cause marring on the inside of the lower receiver.
Therefore, a need exists for a new and improved pistol magazine adapter that enables a standard mil spec AR-15/M-16-style rifle lower receiver to use a Glock® pistol magazine. In this regard, the various embodiments of the present invention substantially fulfill at least some of these needs. In this respect, the pistol magazine adapter according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of enabling a standard mil spec AR-15/M-16-style rifle lower receiver to use a Glock® pistol magazine.